Get the selected item in dropdownlist to display relevant data in label & textbox (sqlServer, c#, VWD)

Could some-one help me please!.  I've spent a while working this out & my asp.net & c# skills are still "underdevelopment",
but the following code is my latest attempt:

What I'm trying to do:

1) User selects a tutor name from a type-ahead dropdownlist (resides in Tutor table of sqldb) - THIS WORKS

2) The selected tutors details (held in another table of same db) populates labels & textboxes
(I do not use sqldatasource or gridview, & at this stage I don't want to use any more js or ajax) - THIS DOESN'T WORK.

I'm using Visual Web Developer, asp.net 2.0, sqlServer 2005, c#

//aspx.cs
using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;
using Sys ...